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Just checking in. Trying to figure how to post.
Noob to the forum. Had my 404S for a few years now. She just got a fresh set of 10.5x20 MPTs. Still working out some timing issues. Just installed Pertronix setup yesterday. Think my advance mechanism is froze up. Timing light says over 40 advanced at idle. View attachment 2627736
here’s a picture of the points. Very rusty. As was the base plate. Just assuming the centrifugal advance froze up. But wasn’t sure what I would getting into when removing the base plate. Any advice on removing the base plate.
29921173-0852-4715-AC64-C755A48A2221.jpeg
 

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The base plate is held in place by 3 small screws around the circumference of the distributor. Underneath the base plate you will find the advancing rotor, advance weights, springs, clips, washers, and sliding pad, on top of the rotor shaft. The sliding plate is beneath the weights (a phenolic plate, now available as a teflon plate) and is suppose to allow the advancing weights to smoothly extend and retract. Often the clips/washers on the weight posts are rusted and providing erratic movement. Once you have the weights/etc out, you can punch out the roll pin holding the bottom pronged hub to the shaft and pull the entire rotor shaft out of the housing for cleaning/replacing the felt pad pad supplying the shaft bearings.




Torn down distributor (bottom row replacement parts kit):
 

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'76 1300L,HE351CW,H15P Winches,Konis,Hydraulics,All Gears,10mm Plungers,Aftercooler,Lots of Littles
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All new belts, runny stuff, and filters.

New front TT Boot (seriously, I have questions for someone who knows something about this as to which ones are worth the trouble to install, because Mabenz doesn’t know...)

Rebuild the Air Filter/Dryer/Blow off contraption. Was building to 20 bar randomly. Cleaned and put it back together. Seems happier.

Reduced the max fueling 1 turn, and put the weights in the govener back at 1 click over stock.

Took it for a test drive on old Hwy105. Openned it up more than I have before (Gravel Road...uphill... big sweepers... Unidrift....) Happy with he way the fuel comes on, finally. Probably fueling for around 215 HP at 1500rpm based on my notes of the bench adjustment.

Short version gearbox conclusion is that the wide ratio box is the better setup in the back, with the close ratio main planetary...4th and 5th are basically the same, but the, practical, 7 speed, is the best road ratio set for a high HP Mog. OR at least the best of the ones I have any way to mess with. :)

C.
 

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The base plate is held in place by 3 small screws around the circumference of the distributor. Underneath the base plate you will find the advancing rotor, advance weights, springs, clips, washers, and sliding pad, on top of the rotor shaft. The sliding plate is beneath the weights (a phenolic plate, now available as a teflon plate) and is suppose to allow the advancing weights to smoothly extend and retract. Often the clips/washers on the weight posts are rusted and providing erratic movement. Once you have the weights/etc out, you can punch out the roll pin holding the bottom pronged hub to the shaft and pull the entire rotor shaft out of the housing for cleaning/replacing the felt pad pad supplying the shaft bearings.




Torn down distributor (bottom row replacement parts kit):
That is an awesome rebuild you got going there. Do you have a source for that parts kit. I looked at EI, but didn’t see one.
 

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The Bosch distributor used in the 404 is very similar/the same base as the model used is various Porsche (356/912) and VW engines of the era, just different springs/weights for a different advance curve. So the respective aluminum (vs. cast iron) distributor rebuild kits largely contain the correct parts.

I picked up my parts from Stodard, though various kits are also available from NLAparts, Pelican, Zim, etc. The weight sliding surface plate is part# NLA-602-102-00 (now changed to NLA-602-102-01). I can't find it in my notes, but I believe the washer shim kit was part# NLA-602-101-50. I took a picture and detailed the contents at the time... but some how I didn't take a picture of the package....


Edit: From a previous post here on BW, the shim kit was also known as Bosch # 1-237-010-007.
 

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1250v
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I started putting it back together, hopefully I will be able to drive it out of the shop for the first time in a few months. The truck got rebuilt rear brakes, new brake lines, the 12.5 x 20 tires mounted, replaced the valve stems with a size that won't hit the brake calipers, and I'm mostly done adjusting the shift linkage. I'm hoping for more than 3 gears! Haha
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U1000Ag
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Finaly got around to calibrating my tacho. I had to cobble together a crankshaft counter using a magnetic pick-up and my digital oscilloscope to get the true crank speed. Showed that the tacho was 5% fast. Alternator pulleys comes in very limited sizes, fortunately this unit has a calibration button on the back - worked perfectly - just upped the perfection score a tiny bit on this Mog :)
This tach is in fact a VDO/Siemens marine tacho/hourmeter that I picked up at a bargain price some years ago. VDO service was great in that they supplied me with the instruction manual which was missing from the sale. Pleased with it - time for a sundowner (Covitini) :p

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2633245
 

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1986 U1300L Expedition Camper
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Nice work. Why did you need to replace the OEM tach? Can we see a pic of it installed in your dash?
 

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U1000Ag
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Nice work. Why did you need to replace the OEM tach? Can we see a pic of it installed in your dash?
Sure - there are a few pics in my steering thread - somewhere ! My old instruments were tired and it was cheaper to just replace everything with NOS. I did fab a new backplate using 5mm thick G10/FR4. It also meant I could accommodate the aubers in a seamless way. - more here Square Cab Dash Paint
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'76 Case MB4/94, '76 U1500 Ag Spec.
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Some days its the little things, especially when it goes smoothly.

A previous owner cut the lower hooks off the Case deck on my 406, and put a Mercedes style 3 point hitch on the rear. The upper hooks were left in place, and it always severely the upper limit of the travel, to the point of almost dragging the flail mower on the ground.

Well, today I fixed that! Cut the upper hooks off with a sawzall (which worked surprisingly well), and clocked the upper lift arms up a bit. I was afraid I was going to have to get a puller, take the rear wheels off, to move those lift arms. Pleasantly surprised when I was able gently tap them off and slide them on by hand. Now the mower is ~18 inches off the ground!

IMG_20200520_184802.jpg
 

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1976 406 w/ backhoe and dozer blade, a small collection of implements too
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Nothing ever goes smoothly! That's great news. Good show.

Of note, I installed a double action hydraulic cylinder in place of the typical upper link which has been a great upgrade. I can adjust the cutting height of my mower on the fly and of course with other attachments, such as the forks, the hydraulic top link is really handy.
 

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'76 Case MB4/94, '76 U1500 Ag Spec.
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Of note, I installed a double action hydraulic cylinder in place of the typical upper link which has been a great upgrade. I can adjust the cutting height of my mower on the fly and of course with other attachments, such as the forks, the hydraulic top link is really handy.
That's on the list, but need a splitter for more circuits back there first. I believe I even have a cylinder laying around. One of these days....
 

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1976 406 w/ backhoe and dozer blade, a small collection of implements too
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That's on the list, but need a splitter for more circuits back there first. I believe I even have a cylinder laying around. One of these days....
I'm kinda hijacking here but "What I did on a PREVIOUS day for my Unimog" is the splitters on the front of the truck and another splitter in the rear for tipper operation.

Though not using the hydraulic top link right now, threw in a picture of the mog with sickle bar mower on it cause folks like pictures.
 

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'91 U1250 '02 U500NA
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New tie rod ends

I was going to replace the whole tie rod first.
Some of you may remember me, trying to import it from US, but looking twice under the truck,
I noticed there were two ends on the rod, left and right, and that made me think.
EPC for UGN NA shows only the entire rod as part, so it took me a while to dig out the actual part numbers for rod ends.
Once having those numbers, there was more of web browsing, but it was worth the time, as I found them German made by
Meyle, for 15 Euro each. I can live with that.
I'm a bit sore today from all that yesterday's wrenching and hammering, but I got it done.
I have to mention my neighbor, who is HD mechanic, and his tips and tricks make always my job easier.
Old ones.jpg
Driver Side.jpg
Passenger side.jpg
 
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